Oxidation of Ni and Ni-5% W


Oxidation of cube textured (100) <001> Ni and Ni-5%W foils were studied in order to verify ifNiO surfacelayer could be fonned on Ni-W similar to that Ni. The principle aim of this study is to prescribe the basic conditions forgrowing a compact, adherent, smooth, and cube texture NiO suitable to be used as a buffer layer in coated conductor,high temperature superconductor architecture. It was found that for Ni 30Jlm thick (002) NiO were fonned at oxidationtemperature of 1250 ± lOoe in air for 60 min. Under the same oxidation condition, (002) NiO with duplex-typemorphology was fonned on Ni-5%W which reduces the mechanical integrity of the sample. Furthennore, due to oxygendiffusion during the oxidation process, spherical NiW04 fonned inside the Ni-W substrate.Keywords: Oxidation, nickel, nickel oxide, nickel-tungsten, rolling assisted biaxially textured substrateZ. Lockman\ M. H. Jamaluddin\ R. Nast2I School of Materials and Mineral Resources Engineering, Universiti Sains Malaysia,14300 Nibong Tebal,Penang, Malaysia,2Forschungszentrum Karlsruhe, Institut fur Technische Physik, Karlsruhe, Germany